1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
liraira [26]
3 years ago
6

Glycolic acid, which is a monoprotic acid and a constituent in sugar cane, has a pKa of 3.9. A 25.0 mL solution of glycolic acid

is titrated to the equivalence point with 45.4 mL of 0.020 M sodium hydroxide solution. What is the pH of the resulting solution at the equivalence point
Chemistry
1 answer:
slava [35]3 years ago
8 0

Answer:

pH of resulting solution = 7.98

Explanation:

The balanced equation  

HA + NaOH - Na+ + A- + H2O

Number of moles of A = Number of moles of HA  = Number of moles of NaOH

= 35.8/1000 * 0.020 = 0.000716 mol

Initial concentration of A = 0.000716/0.0608 = 0.01178 M

pKb = 14 – pKa = 14 -3.9 = 10.1

Kb = 10^{-Kb} = 10^{-10.1} = 7.943 * 10^-11

Kb = [HA][OH-]/[A-]

Kb = a^2/(0.01178 -a) = 7.943 * 10^-11

a^2 + 7.943 * 10^-11 a – 9.357 * 10^-13 = 0

a = 9.673 * 10^-7

OH- = a = 9.673 * 10^-7 M

pOH = -log [OH-] = -log (9.673 * 10^-7) = 6.02

pH = 14-6.02 = 7.98

You might be interested in
The number of protons present in ATOM 1 is______
Ira Lisetskai [31]
Three protons and three electrons. The protons are the plus signs because protons are positively charged, and the electrons are the minus signs because electrons are negatively charged. Also, the neutrons are the circles. Neutrons are negatively charged
7 0
3 years ago
Read 2 more answers
The second-order rate constant for the dimerization of a protein (P) P + P → P2 is 6.2 × 10−3/M · s at 25°C. Part 1 out of 2 If
siniylev [52]

Answer:

r=1.59\times 10^{-10}\ M/s

Explanation:

According to the law of mass action:-

The rate of the reaction is directly proportional to the active concentration of the reactant which each are raised to the experimentally determined coefficients which are known as orders. The rate is determined by the slowest step in the reaction mechanics.

Order of in the mass action law is the coefficient which is raised to the active concentration of the reactants. It is experimentally determined and can be zero, positive negative or fractional.

The order of the whole reaction is the sum of the order of each reactant which is raised to its power in the rate law.

From the reaction given that:-

P+P\rightarrown P_2

The expression for the rate is:-

r=k[P]^2

Given that;- k= 6.2\times 10^{-3} /Ms

[P] = 1.6\times 10^{-4} M

Thus,

r=6.2\times \:10^{-3}\times \:\left(1.6\times \:\:10^{-4}\right)^2\ M/s=1.59\times 10^{-10}\ M/s

8 0
3 years ago
11. Which of the following elements CANNOT violate the octet rule?
rjkz [21]

Answer:

I think it's Nitrogen is right answer

8 0
3 years ago
Read 2 more answers
When 3-methyl-1-pentene is treated with in dichloromethane, the major product is 1-bromo-3-methyl-2-pentene.
Lubov Fominskaja [6]

Answer:

True

Explanation:

When Methyl Pentene is introduced in a chemical reaction with dichloromethane then the major product will be bromomethylpentene. There can be small amount of bromo methyl pentene than the amount of methyl pentene introduced for reaction.

3 0
3 years ago
What is the particle theory
kolezko [41]

Answer:

The kinetic theory of matter (particle theory) says that all matter consists of many, very small particles which are constantly moving or in a continual state of motion. The degree to which the particles move is determined by the amount of energy they have and their relationship to other particles.

Six main points of the particle theory:

• All matter is made of particles.

• Particles have space between them.

• Particles are always moving.

• Particles move faster and get farther apart when heated.

• Particles are attracted to each other.

• All Particles of the same substance are identical

7 0
3 years ago
Other questions:
  • A student is asked to convert measurements from grams to kilograms and from kilograms to grams. His answers are shown in bold in
    10·1 answer
  • Which integumentary system structure produces sebum that lubricates the hair and
    13·1 answer
  • What kind of electrochemical cell might likely be used for a task such a electroplating?
    12·2 answers
  • 1. The solubility of AgNO3 at 20°C is 222.0g AgNO3/100g H2O. What mass of AgNO3 can be dissolved in 250 g of water at 20°C? Reca
    12·1 answer
  • What is the temperature, in degrees Celsius, of a substance with a temperature of 49K? –322°C –224°C 224°C 322°C
    5·1 answer
  • The addition of heat causes the individual particles of a solid to
    13·1 answer
  • Using the equation below, calculate the approximate moles of oxygen gas (O2) required to completely react with 719.68 moles of a
    11·2 answers
  • What is the mass of 2.30x10^22 formula units of NaOH (molar mass =40.0g/mol)
    6·1 answer
  • Acid-Base Chemistry 1:Question 10
    10·1 answer
  • A 2.684-g sample of zinc oxide was reduced by hydrogen gas, resulting in 2. 156 g of pure zinc metal. Determine the empirical fo
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!